"We
know that antibiotic prescribing, particularly to patients who are not likely
to benefit from it, increases the prevalence of antibiotic-resistant bacteria,
a growing concern both here in the United States and around the world," said Jeffrey A. Linder, MD, MPH, a physician and researcher in
the Division of General Medicine and Primary Care at BWH and
senior author of the paper. "Our research shows that while only 10 percent of
adults with sore throat have strep, the only common cause of sore throat
requiring antibiotics, the national antibiotic prescribing rate for adults with
sore throat has remained at 60 percent. For acute bronchitis, the right
antibiotic prescribing rate should be near zero percent and the national
antibiotic prescribing rate was 73percent."

Linder
and lead author, Michael L. Barnett, MD, measured changes in the prescribing of
antibiotics for adults with sore throat and acute bronchitis using nationally
representative surveys of ambulatory care in the United States from 1996 -
2010. The data represented an estimated 39 million acute bronchitis and
92 million sore throat visits by adults to primary care clinics or emergency
departments.

The
researchers found that although visits for sore throats decreased from 7.5
percent of primary care visits in 1997 to 4.3 percent of visits in 2010, the
overall national antibiotic prescribing rate did not change with physicians
prescribing antibiotics at 60 percent of visits. There was no change in
the percentage of emergency department visits for sore throat during the time
period (2.2-2.3 percent). The number of acute bronchitis visits increased from
1.1 million visits in 1996 to 3.4 million visits in 2010.

The
data also show that prescriptions of penicillin, the antibiotic recommended to
treat strep throat, remained at 9 percent while prescribing for azithromycin, a
more expensive antibiotic, increased from being too infrequent to measure reliably in1997-1998 to 15 percent
of visits in 2009-2010.

The
researchers also noted an increase in the antibiotic prescribing rate in
emergency rooms, from 69 percent to 73 percent, during the same 14-year period.

"In
addition to contributing to the prevalence of antibiotic resistant bacteria,
unnecessary use of antibiotics also adds financial cost to the health care
system and causes adverse effects for those taking the medication," said
Barnett. Most sore throats and cases of acute bronchitis should be
treated with rest and fluids and do not require a visit to the doctor," he
added.

In
light of these findings, research efforts are now underway to develop and
implement interventions that reduce inappropriate antibiotic prescribing for
respiratory infections.

Dr.
Linder's work on acute respiratory infections is supported by grants from the
National Institutes of Health (RC4 AG039115), the National Institute of Allergy
and Infectious Diseases (R21 AI097759), and the Agency for Healthcare Research
and Quality (R18 HS018419).